system.net.mail requires starttls

how to I fix I get an error that it requires a starttls
Imports System.Net.Mail
Public Class Form1
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Try

            Dim SmtpServer As New SmtpClient()
            Dim mail As New MailMessage()
            SmtpServer.Credentials = New Net.NetworkCredential("me@gmail.com", "password")
            SmtpServer.Port = 587
            SmtpServer.Host = "smtp.gmail.com"
            mail = New MailMessage()
            mail.From = New MailAddress("me@gmail.com", "my name")
            mail.To.Add("me@hotmail.com")
            mail.Subject = "Test Mail"
            mail.Body = "This Is for testing SMTP mail from GMAIL"
            SmtpServer.Send(mail)
            MsgBox("mail send")
        Catch ex As Exception
            MsgBox(ex.ToString)
        End Try
    End Sub
End Class
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HalCHubAsked:
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Michael FowlerSolutions ConsultantCommented:
try setting enableSSL to true

SmtpServer.EnableSsl = true;

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https://msdn.microsoft.com/en-us/library/system.net.mail.smtpclient.enablessl.aspx
HalCHubAuthor Commented:
nope here is a different version

    Private Sub test(Optional ByVal smtp As String = "smtp.gmail.com")
        Dim toAdd As String = " test@gmail.com"
        Dim fromAdd As String = "test@gmail.com"
        Dim pass As String = "pswd"
        Dim client As SmtpClient = New SmtpClient(smtp)
        Dim mail As New MailMessage
        mail.From = New MailAddress(fromAdd)
        mail.To.Add(toAdd)
        mail.Subject = "Test Zip File"
        mail.Body = "This Is just a test"
        client.Port = 465 '465 587  25
        client.Credentials = New System.Net.NetworkCredential(fromAdd, pass)
        client.EnableSsl = True
        MsgBox("here")
        '   client.Timeout = Int32.MaxValue
        Try
            client.Send(mail)

        Catch ex As SmtpException
            MsgBox(ex.Message)
        End Try
        MsgBox("done")
    End Sub

port 465 times out
port 25 gives a starttls error
port 587 give required secure connection
Michael FowlerSolutions ConsultantCommented:
Your code looks fine, assuming you are using a valid email/user/pass in your actual code.

This google support article has more ideas for testing
https://support.google.com/mail/answer/78775?hl=en

The first is to confirm that you can log into the account you are using manually and so validate your credentials

Another good test is telnet to confirm that a connection can be made from your machine
eg telnet smtp.gmail.com 587
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Rafiq J.Net DeveloperCommented:
<network host="smtp.gmail.com" enableSsl="true" ... />
Rafiq J.Net DeveloperCommented:
Rafiq J.Net DeveloperCommented:
try this logic

 string fromaddr = "YOURMAILID@gmail.com";
        string toaddr = TextBox1.Text;//TO ADDRESS HERE
        string password = "YOUR PASSWROD";


        MailMessage msg = new MailMessage();
        msg.Subject = "Username &password";
        msg.From = new MailAddress(fromaddr);
        msg.Body = "Message BODY";
        msg.To.Add(new MailAddress(TextBox1.Text));
        SmtpClient smtp = new SmtpClient();
        smtp.Host = "smtp.gmail.com";
        smtp.Port = 587;
        smtp.UseDefaultCredentials = false;
        smtp.EnableSsl = true;
        NetworkCredential nc = new NetworkCredential(fromaddr,password);
        smtp.Credentials = nc;
        smtp.Send(msg);


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